That's why Florida recently activated a sign-up email system that sends out notifications whenever a local law enforcement officer is killed, has suffered an injury or is missing while on duty — and a suspect is at large.

Residents simply sign up at bluealert.imarcsgroup.com to be able to receive a Blue Alert via email, along with up-to-the-minute information, such as a suspect's vehicle description and license plate number.

Also check out the Florida Department of Law Enforcement website (at http://www.fdle.state.fl.us) to find out more about the state's Silver Alert Plan, which uses highway signs to ask residents to look out for missing senior citizens or their cars.